Has anyone run in to problems using Navionics Platinum chips in Lowrance units? I bought a couple chips for my X-27 and 520 and was ready to throw them both overboard last weekend when they'd make my units freeze before shutting them down. I've heard of some similar issues but nothing like this.

I did, however, get them to work in both units (3 days after I needed them). I'd just like to know if this is an isolated incident.

I have not had any problems. If the units are used you might want to go to their site and see if they have been updated. If not that could be a problem.  Go to the site and they willl give you directions on how to see if they are running the most updated programming. Can't remember off the top of my head, but I think it will say in your unit that you are running 1.5 or 5.0 and if your unit tells you something else you need to update. JMO

He has to have the latest update installed because it added Navionics Platium support with it.  I have had the same issue trying to demostrate them at my work.  Sometimes it works, sometimes it locks up the unit and you have to remove the power cord to reboot it.  I hope with time they will get the kinks worked out.

No issues at all. I'm running 2 Lowrance 520c units linked together with the new 2008 Platinum chip in the dash mount unit. I had to update the firmware on the unit to version 2.3.0 before the chip would work. I send Lowrance $8 and they sent me a chip loaded and ready to go. I put it in, powered it up, it updated, took it out, powered it down, put the new chip in, and it works fine. The new 3D stuff is amazing. The photos are not that useful but the 3D overlay is out of sight. Really great stuff. Lowrance is supposed to come out with something this year that will put Side Imaging on its ear. Hope they can actually pull it off.